Composite lipid emulsions containing soybean oil (30%), medium-chain triglycerides (30%), olive oil (25%), and fish oil (15%) (SMOF) are now widely used. We aimed to evaluate the tolerance, the efficiency, and the erythrocyte fatty acid (FA) profile for children on long-term home parenteral nutrition (HPN) receiving a composite fish oil-based emulsion (FOLE). At baseline, children (n=46) with severe intestinal failure highly dependent on parenteral nutrition (PN) for ≥1 y were included in the study when they had received the composite FOLE for >6 mo. Out of this baseline group, only 25 children remained highly PN-dependent (SMOF1, n=25) and could be assessed a second time, 2.4 y later (SMOF2, n=25). An independent control group ("weaned off PN" group; n=24) included children who had been weaned off PN for >2 y (median: 4 y). RBC-FA composition was established by GC-MS. Growth parameters, plasma citrulline, conjugated bilirubin, FA profiles, and the Holman ratio (20:3ω-9/20:4ω-6) were compared between groups. No difference for growth parameters, citrulline, and bilirubin was observed between the SMOF groups after 2.4 y (0.2<P<0.8). The weaned-off group did not differ from the SMOF groups for growth parameters (0.2<P<0.4) but citrulline was higher (P<0.0001) and conjugated bilirubin lower (P<0.01). The composite FOLE induced higher proportions of EPA (20:5n-3) (8.4%±2.9%) and DHA (22:6n-3) (11.7%±2.2%) than what was observed in weaned-off children (0.8%±0.4% and 6.6%±2.3%, respectively) but lower proportions of arachidonic acid (20:4n-6). However, the Holman ratio did not vary between groups (P=0.9), whereas the PUFA concentrations varied widely. Long-term use of the composite FOLE was well tolerated in HPN-dependent children. The RBC-FA profile alterations were consistent with the ω-3 PUFA-enriched composition of this emulsion without evidence of essential FA deficiency.